Domestic appliance



July 10, 1962 B. 1.. BRUCKEN DOMESTIC APPLIANCE 3 Sheets-Sheet 1 FiledMarch 27, 1958 INVENTOR.

Byron L Bracken BY HIS ATETOREY 3 Sheets-Sheet 2 w e .T\ w 1 a, Z 2 .l

INV ENT OR. Byrd); Z Bracken BY B. BRUCKEN DOMESTIC APPLIANCE July 10,1962 Filed March 27, 1 958 July 10, 1962 B. L. BRUCKEN DOMESTICAPPLIANCE 5 SheetsSheet 3 Filed March 27, 1958 1 H W. U/ m i a,s43,015Patented July 10, 1962 3,043,015 DOMESTIC APPLIANCE Byron L. Bracken,Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich., acerporation of Delaware Fiied Mar. 27, 1958, Ser. No. 724,366 Claims.(61. 34-80) This invention relates to a domestic appliance and moreparticularly to an improvement in adsorbent clothes dryers.

In conventional clothes dryers it is the procedure to flow an amount ofheated air through a chamber full of clothing that is being tumbledtherein. In this manner the length of time necessary to dry the clothingis dependent generally upon the amount of heat which is supplied to theair being circulated through the clothes drying chamber. Where the heatutilized in such a clothes drying process is generated from a normalresidential source of power, such as electricity, the amount of heatinput available for the clothes drying is limited by the capacity of thepower supply. It has been proposed to supplement the heat available fora clothes drying operation from a conventional power supply with heatgiven up by an adsorbent process. The heat evolved in such an adsorbentprocess is denoted as a heat of condensation and a heat of wetting. Amore complete explanation of the adsorbent clothes drying concepts areset forth in copending application Ser. No. 689,570, filed October 11,1957, wherein a solid adsorbent or desiccant is disposed in the flowpath of the drier air.

In the operation of a clothes dryer using a solid adsorbent 'to removethe moisture from the air being re circulated through the dryer, certaindisadvantages ap pear. For one thing, a reasonably large amount of solidadsorbent must be used to adsorb the quantity of moisture found normallyin a dryer load of damp clothes. This creates space problems within thedryer cabinet. Furthermore, since the solid adsorbent intercepts orfilters substantially all of the air being recirculated through thedryer, dryer use over an extended period will cause a build-up-of verysmall lint particles on the surface of the solid adsorbent. Such lintbuild-up impedes air flow and fosters a generally lessening efficiencyof the adsorbing process, in particular, and the dryer operation ingeneral.

Servicing problems, too, are created with the use of solid adsorbentswhich are necessarily bulky. For this reason dryer cabinet design mustprovide for replacing the solid adsorbent, and thus add to manufacturingcosts;

Accordingly, it is-an object of this invention to use a liquid adsorbentor hygroscopic material which has a higher moisture adsorbing capacitythan have the solid adsorbents.

It is also an object of this invention to provide a liquidadsorbent'distribution system wherein a spray of adsorbent fluid isinterposed in the dryer air stream.

A more specific object of this invention is the provision of a filterinterposed in the dryerair stream and over which liquid adsorb-ent ispumped in a manner to minimize lint build-up which could reduce thedryer flow.

Additional advantages are achieved by this invention in an adsorbentdryer provided with means to facilitate draining of a liquid adsorbentfrom the dryer, whereby lint build-up may be cleaned from the adsorbent.

It is also an object of this invention to provide a clothes dryingsystem which will impart a fabric conditioning to the clothes beingdried.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein a preferred embodiment of the present invention isclearly shown.

In the drawings:

FIGURE 1 is a front elevational view, with parts broken away, of aclothes dryer provided with this invention;

FIGURE 2 is a sectional view taken generally along the line 22 of FIGURE1;

FIGURE 3 is a sectional view taken substantially along line 33 of FIGURE1; and

FIGURE 4 is a schematic wiring diagram setting forth one manner in whichthis invention may be placed in operation.

In accordance with this invention, and with reference to FIGS. 1 and 2,a clothes dryer shown generally at 10 is provided with a liquidadsorbing arrangement shown generally at 12. The dryer 10 is comprisedof side walls 14 16, a front wall 18, a top wall 19 and a rear wall 20.Within the chamber formed between walls 14, 16, 18 and 2% a tumblingdrum 22 is rotatably mounted on a shaft 24 which is supported in auniversal bearing arrangement 26. A bulkhead 28 extends parallel to thechamber 36 is defined by the perforated rear wall 31 of the drum, theimperforate bulkhead 28 and an annular seal 38 of felt or other suitablematerial carried by the bulkhead 28 and in sliding engagement with drumrear Wall 31. A second annular chamber 40 is formed adjacent the outflowports 34 in the drum front wall 29 and is defined by a front bulkhead 42and an annular seal 44 carried thereby. The front bulkhead 42 isinwardly flanged at 46 into underlying concentric relationship with anoverlying flanged neck portion 48 of the tumbling drum, thereby forminga clothes loading access to the tumbling drum interior 27. Axiallyaligned with the openings formed by flanges 46 and 48, is an access door50 hingedly mounted at 5 1 on the front wall 18 of the dryer. Disposedbelow the access door 50, a front duct 52 is arranged in consecutive airflow relationship with the front annular chamber 40 by means of anopening or cutout 54 through juxtaposed front duct wall 53 and bulkhead42. Immediately behind the front duct 52 and in air flow relationshipthereto is a lint disposal housing 55. Within the housing 55,anddisposed to intercept substantially all of the air flowing throughthe duct 52 is a lint collector or disposer 56. Preferably, thecollector 56 includes a lint burning arrangement as taught in copendingapplication S.N. 635,635 filed January 23, 1957, but may be merely ascreen for trapping the lint. To facilitate an occasional cleaning ofthe lint collecting and/ or burning arrangement 56, an access panel 58is arranged to overlie and snap-fasten to an opening 6% in the frontduct 52 and dryer wall 18 through which access may be gained to the lintdisposal arrangement 56. In this construction, a vacuum cleaner may beused 'to remove lint from a collecting screen or 'ash from a lintburner. Connected to the lint disposal housing 55, a passageway orconduit 62 leads to an inlet 64 of blower 66 from which point the blowerdischarges air through an opening 65 into the adsorbent chamber 12, tobe described more fully hereinafter. The air is subsequently, dischargedfrom this chamber through an outlet opening as into a regeneration airexhaust chamber or damper housing 70 which selectively connects eitherto atmosphere through a conduit 138 or to a rear duct 72 through drivethe blower 66 through a shaft 82 while simultaneously rotating thetumbling drum' 22 through the pulley system 30; It 'is, therefore,evident that a recirculating or closed air flow path has been providedwhereby air impelled by the blower 66 proceeds through an adsorbentchamber 12 to arear duct 72. Air then progresses upwardly in duct 72past primary heater 78 where it may be warmed preparatory to enteringthe rear annular chamber 36 and subsequently tumbling drum 22 throughdrum ports 32. As the heated air circulates in a normal drying cycle,the drum 22 is rotated and the clothing placed therein tumbled in thestream of heated is drawn from the interior 27 of drum 22 into the frontannular chamber 40 through ports 34 from which point the air proceedsdownwardly in front duct 52, through the lint disposal housing 55,returning again to blower 66 to complete the closed recirculating airsystem. 7

Reference may now be had to FIGS. 1 and 3 for a more completedescription of the adsorbent chamber '12. The chamber 12 is formed witha sloping top wall 84 which is so configured to fit within the'availablespace beneath the outer periphery of the tumbling drum 22. The chamber12 is further defined by a front wall 86, a rear wall 88 and a blowerinlet wall 90. Thebottom portion of chamber 12 is formed into a liquidcontaining sump 92 which has an enclosed extension or pump housing'94projecting from chamber rear Wall 88. It should be noted that theextended portion 94 is at the lowermost point of the sump 92 since apump 96 resides therein and is driven by a small, fractional horsepowermotor 98 to circulate fluid within the chamber 12. .Carried also withinthe sump 92 is an adsorbent regenerative heater 100, the function ofwhich will be more fully understood hereinafter; Suflice it to say atthis point that the heater 100 serves to boil-off the moisture which theliquid desiccant in sump 92 has adsorbed during the clothes dryingprocess. 1

The sump 92. may also be provided with a drain tube 1512 and a supplytube 104 for servicing the liquid adsorbent, either of which tubes maycarry a valve for convenience. Disposed within the chamber 12 andcompletely filling the area between the liquid adsorbent in sump 92 andthe chamber walls 84, 86 and '88 is a filter 1060f aluminum or othersuitable material. The filter material 106 may be carried in a frame 108which is provided with an opening 110 on either side of the filtermaterial 106. In a top portion of the'filter' frame 108 -a-s'pray headeror sprinkler 112 extends the width of 7 to the. bottom of chamber 12 orsump 92 through inlet 104 until .a' liquid level 105 is reached whichsulficiently' covers the bottom 107 of the filter 'material 106 and regenerativeheater 100. This, then, assures that all air passing throughchamber 12 must necessarily pass through the filter 106; Suitable liquidadsorbents maybe found in the'glycol or glycerol groupsuchas glycerineand V eth ylene glycol. With the motor 9 8 energized, the pump 96 willfunction to circulate the adsorbent fiuid by way of conduit 116 to thespray-header 112, thereby distributing the adsorbent evenly andcontinuously over the surface of the filter material 106. The fluid willthen flow by gravityover the filter fibers until it returns again tosump 92. The pump 96 is circulated continuously during the clothesdrying period. In this regard, while the heated air is picking upmoisture released from the damp clothes tumbling in its path, theadsorbent fluid is being sprayed over the filter 106 in a manner tointercept all of the moisture-laden air being circulated and to therebyadsorb moisture from the air.

After the clothes are dried, it is generally desirable to remove themoisture adsorbed by the desiccant. For this purpose a regenerativeheater 100 is disposed within the sump 92- and submerged in theadsorbing fluid. Although the arrangement here described contemplates aregenerating of the adsorbent at the conclusion of each drying cycle, itshould'be noted that regeneration of the adsorbent is dictated solely bythe moisture adsorbing capacity of the desiccant. Therefore, it shouldbe apparent that an arrangement could easily be devised whereby theadsorbent fluid is regenerated only when it has adsorbed its fullmoisture capacity.

During the regeneration process it is desirable to cease rotating thetumbling drum 22 and to exhaust to the atmosphere any moisture which isbeing heated or boil olf the adsorbent liquid in sump 92. To further thefirst of these aims, a conventional spring clutch 118 is adapted partlyto overlie a drive portion 120 of drum support shaft 24 and partly tooverlie a shaft stub portion 122?. which is integral with pulley hub124. In this respect it should be noted that the shaft stub 122 isdrilled to receive a reduced diameter extension 126 of drum supportshaft 24 to retain the shafts 24- and 122 is concentric, relativelyrotatable relationship. One terminus or boss 128 of the spring clutchprojects radially upwardly into the path of an arm 130 pivotally mountedat 132 to move in response to the action of solenoid 134. With thesolenoid 134 energized, arm 130 is pivoted into blocking engagement withspring clutch boss 128 thereby relaxing the tension of the springconvolutions 118 to allow the pulley system to rotate freely -withoutdriving the tumbling drum 22, i.e.', the pulley shaft'portion 122 merelyidles on drum shaft extension 126.

To effect the exhaust of the moisture-laden air during regeneration ofthe adsorbent, the passageway or damper housing 70, extending betweenthe adsorbent chamber 12 and rear duct 72, mounts'an air outlet stubconnection 136 which projects through the wall of passageway 70.Extending from the stub 1136 to any point outside the dryer 10 is aconduit 138 which is preferably fiexible.-

It should be: noted that conduit 13% may be considerably smaller thanthe conventional: 3" and 4" dryer vents, as outlined more fully in theaforementioned copending application. Disposed the passageway 70, adamper 140, is adapted to overlie and seal outlet stub 136 during normaldryer operation. However, throughout a regeneration cycle, a solenoid142 is energized to pivot damper 140 into air sealing engagement withrear duct outlet 74. Thus, with motor 80 driving blower 66, moistureboiled from the adsorbent in sump 92 is carried through conduit 138 tothe outside atmosphere. Air flow during regenerationis' necessarilyreduced in accordance -with' the size of outlet stub 136 which has beenfound to produce satisfactory air flow when approximately 1 tol /2"indiameter. In addition, sufiicient leakage is found to occur along thesliding engagement 7 between drum 22 and seals 38 and 34 to providemakeup air for the amount exhausted toatmosphere during regeneration; YI

In operation the features of thisinvention will best be understood withreference to the schema-tic wiring diagram of FIG. 4 wherein similarelements carry the '75 until door 50 is closed. Timer-dial (not shown)is then turned to cause a cam 146, within a conventional timer 148 tobias switch blade 158 downwardly into engagement with switch blades 160and 162. In this manner the drying cycle is initiated. The motor orprime mover 80 is energized by way of L line 164, contact blade 158,contact blade 160, line 166, line 168, the motor 80, and the door switch144 to L The main heater circuit includes a safety switch 170, disposedabove the primary heater 78 in rear duct 72 and a cycling thermostat 172disposed in front duct 52. The safety switch 170 serves to eliminatedangerous high temperatures within the heater chamber, while thethermostat i172 operates to cycle the heater 78 in maintaining aselected drying temperature within the tumbling drum 22. As a furtherassurance against undue temperature rise within the dryer, a motorinterlock switch 174 actuated centrifugally by the rotation of motor 80is closed whenever the motor is in operation. With the components justdescribed in circuit and the dryer dial set as aforesaid, the mainheater 78 will be energized from L through line '164, timer blade 158,timer blade 160, timer blade 162, line 176, heater control switches 170and 172, safety switches 144 and 174 to the other side of the line L Thepump motor 98 is similarly energized but bypasses the heater controlswitches 170 and 172. In this same operation, the timer motor 178 isenergized from L line 164, timer blade 158, timer blade 1160, line 166,line 188, switch 182, the timer motor and line 184, switches 144 and174, to L This timer induced relationship of the pump motor 98, heater78 and motor 80 maintains throughout the time interval selected on thetimer 148.

Immediately upon energization of motor 80, a thermal relay 186 isenergized to close a switch 188 in the regeneration circuit. At theconclusion of the drying cycle, timer cam 146 will cause timer blade 158to disengage timer blades 168 and 162 and permit engagement withregeneration circuit contact v190. The regeneration circuit includes anormally closed thermostat 192 which operates to terminate theregeneration process. A second thermostat 194 may be included within theadsorbent sump 92 to insure against explosion hazards or excessiveoverheating of the liquid adsorbent. In this regard the thermostat 194will act to open the circuit leading to the regenerative heater 100.

With the clothes drying cycle completed and the dryer contacts disposedto place timer blade 158 in engagement with contact 190, a solenoid 196is thus energized by way of L line 164, timer blade 158, timer contact190, regenerative thermostat 192, thermal relay actuated. regenerativecircuit arming switch 188, line 198 to L This energization of solenoid196 will reverse the positions of switches 200, 202 and 182 from thoseshown in FIG. 4. Thus, the timer motor will be prevented from operatingduring regeneration by open switch 182. However, the regenerationprocess will be initiated from L timer blade 158, contact 190, solenoidswitch 202, solenoid switch 280, line 204, sump high limit thermostat194, regenerative heater 100 to L through motor safety switch 174 anddoor switch 144. In the same circuit relationship solenoid 134 will beenergized to relax the action of spring clutch 118 on shaft segment 120of drum shaft 24 to per? mit the drum 22 to remain motionless, whilemotor 80 operates to drive the blower 66 in exhausting moistureladenair. Furthermore, solenoid 142 is energized at the same time to placeexhaust damper 140 in air flow sealing relationship to the rear ductopening 74, as shown in phantom in FIG. 3. During the regenerationprocess the motor 80 continues to operate, receiving power from L line164, timer blade 158, contact 190', solenoid switch 202, line 180, line168, door switch 144 to L The blower 66 thus continues to operate,sending a reduced air flow through the adsorbent chamber 12 due to therestricted air exhaust outlet afforded by the conduit 138. As the heater100 boils off the moisture from the liquid adsorbent, the reduced airflow carries this moisture from 8 chamber 12 by way of outlet 68 andthrough stub outlet 136 to the exhaust conduit 138.

In the regeneration process, temperatures will remain substantiallyconstant within the air above the liquid sump while the moisture isbeing given up by the adsorbent. As

this process nears its termination, the sensible temperature of the airwill rise markedly to open the regeneration thermostat 192, therebyterminating the regeneration process and placing the timer 148 incondition for a sub-' tating means, means to spray an adsorbent fluidinto the air leaving said drum to increase the temperature of said air asecond amount without energization from said external power source, sumpmeans for receiving said adsorbent fluid, second heating means adjacentsaid sump means for regenerating said adsorbent fluid, and meansincluding air flow reduction means for discharging air periodi callyfrom said aid duct system concurrently with the energization of saidsecond heating means.

2. A clothes dryer, including an outer cabinet, a tumbling drumrotatable in said cabinet, means for rotating said drum, means fordisconnecting said drum from said rotating means, said tumbling drumhaving perforated front and rear walls, a front duct in communicationwith said front wall, a rear duct in communication with said rear wall,first heating means in said rear duct, an adsorbent distribution systemincluding a spray chamber, a sump in said chamber, anadsorbent in saidsump, spray means above said sump and in air flow interceptingrelationship between said front and rear ducts and adsorbent circulatingmeans connecting said sump to said spray means, second heating meansassociated with said sump, a blower having aninlet connected to saidfront duct and operable to circulate air in a closed circuit includingsaid tumbling drum, said spray chamber and said rear duct, bypass meansincluding a damper between the spray chamber and said rear duct forselectively blocking said rear duct to discharge air from said closedcircuit, and a circuit means including a timer for concurrentlydeenergizing said first heating means and energizing said second heatingmeans, said disconnecting means, said bypass means and said blower aftersaid clothes are dried for regenerating said adsorbent.

3. A clothes dryer, including, a drum for said clothes, means to rotatesaid drum, means providing a closed circuit air system incorporatingsaid drum, heating means for said drum, means for circulating airthrough said air duct system, a liquid adsorbent arrangement adapted tofilter air leaving said drum including a sump for said adsorbent, afilter element and means for directing said adsorbent over said filterelement, heating means adjacent said sump for regenerating said liquidadsorbent, means including air flow reduction means in said duct systemfor discharging air periodically from said air duct system concurrentlywith the energization of said heating means for regenerating said liquidadsorbent, and means to interrupt the rotation of said drum during saiddischarge.

4. In combination, a clothes dryer having a cabinet, a perforated drumrotatably supported in said cabinet, means for selectively rotating saiddrum including a power driven shaft secured to said drum and rotatabletherewith and a spring clutch on said shaft adapted for unidirectionalshaft rotation, means providing a normally closed air flow systemincluding said drum, a duct and a fan for circulating air through saidduct and said drum, a first heater in said closed system for aiding inthe removal of moisture from said clothes, means for collecting lintfrom said air, an adsorbent fluid arrangement for removing moisturefrom'said air including an adsorbent fluid, a spray means in said duct,a sump and a pump for circulating said fluid from said sump to saidspray means and into moisture removing relationship to said air, afilter in said closed system over which said fluid is sprayed, a second'heater in said sump tor aiding in the subsequent removal or moisturefrom said adsorbent fluid, a relatively small bypass connected to saidduct downstream from said sump and openable to said duct concurrentlywith the energization of said second heater for periodically dischargingto the outside atmosphere the moisture removed from said air, and meansfor terminating the rotation of said drum during the opera- 1 tion ofsaid second heater.

tionship between said front and rear ducts for removing moisture fromthe airflow intercepted and depositing said moisture in saidsump,"second heating means associated with said sump, a blower having aninlet connected to said front duct and operable to circulate air heatedby said first heating'means in a closed circuit including said tumblingdrum, said moisture removal chamber and said rear duct to removemoisture from said clothes, bypass means including a damper between themoisture removal chamber and said rear duct for selectively dischargingair from said closed circuit, and a circuit means including a timer forconcurrently deenergizing said first heating means and energizing saidsecond heating means and said bypass means after said clothes are driedfor removing'the moisture from saidclothes dryer to the atmosphere.

References Cited in the file .of this patent UNITED STATES PATENTS910,525 I Gardner Jan. 26, 1909 2,066,847 McShe'a Jan. 5, 1937 2,162,158Coey June 13, 1939 2,249,624 Bichowsky July 15, 1941 2,675,628 ONeilApr. 20, 1954 2,695,450 Clark Nov. 30, 1954

